Lecture 8 - Oesophageal function

Question 1

3 phases and muscles involved in swallowing?

Answer 1

Oral - striated (voluntary); Pharyngeal - straited (involuntary); Oesophageal - striated and smooth muscle (involuntary)

Question 2

Swallowing nervous reflex?

Answer 2

Brainstem recieves sensory input from receptors in posterior mouth and upper pharynx, then innervates swallowing muscles via cranial nerves

Question 3

Oral phases?

Answer 3

Preparatory: formation of bolus; Transfer: Bolus propelled into pharynx

Question 4

3 parts of pharynx?

Answer 4

Nasopharynx, Orophrynx, Hypopharynx

Question 5

Pharyngeal Phase: Sealing back of mouth?

Answer 5

tongue pushes against palate to seal oropharynx

Question 6

Pharyngeal Phase: Sealing upper airway?

Answer 6

Soft palate elevates and proximal pharyngeal wall move medially to seal nasopharynx

Question 7

Pharyngeal Phase: Sealing lower airway?

Answer 7

Epiglottis swings down, vocal cords adduct to seal lower airway

Question 8

Muscles of opening UOS?

Answer 8

Cricopharyngeus, Suprahyoid, Thyrohoid

Question 9

Oesophagus length and muscle distribution?

Answer 9

20-25cm long; 1/3 skeletal, bottom 2/3 smooth

Question 10

Primary Peristalsis?

Answer 10

Initiated by swallowing, continuation of pharyngeal contraction wave, slower than pharyngeal peristalsis

Question 11

Secondary Peristalsis?

Answer 11

Initiated by distension, stimulated stretch receptors initiate local reflex response triggering peristalsis

Question 12

Squamocolumnar Junction?

Answer 12

Transition between squamous epithelium of oesophagus and columnar epithelium of stomach

Question 13

Lower Oesophageal Sphincter compared to upper (and innervation?

Answer 13

Normally closed also, much lower pressure than UOS, can relax when not swallowing to release air from stomach, innervated by vagus nerve

Question 14

Manometry?

Answer 14

Catheter w pressure sensors inserted while patient swallows water

Question 15

Gastro-oesophageal reflux?

Answer 15

During transient opening of LOS, stomach acid moves into the oesophagus

Question 16

Causes of Gastro-oesophageal reflux?

Answer 16

Hypotensive LOS (diet or drugs), some Hiatus hernias, Impaired oesophageal peristalsis

Question 17

Hiatus Hernia?

Answer 17

Part of the stomach protrudes through the hiatus - or opening of the diaphragm supporting muscle

Question 18

Symptoms of G-O reflux?

Answer 18

burning sensation due to pH sensitive nerve fibres, eventual complications through chronic acid exposure, regurgitation, sour/bitter taste

Question 19

Reflux oesophagitis?

Answer 19

Oesophageal mucosa damage leading to inflammation, ulcers and bleeding

Question 20

Peptic stricture?

Answer 20

Prolonged inflammation leading to fibrosis and scarring

Question 21

Difficulty swallowing technical term?

Answer 21

Dysphagia

Question 22

Barrets oesophagus?

Answer 22

Chronic acid exposure transforms squamous epithelium into columnar epithelium - intestinal metaplasia; risk of adenocarcinoma

Question 23

Risks for squamous cells carcinoma?

Answer 23

smoking, diet, drinking

Question 24

Differences between adenoCa and SqCC?

Answer 24

SqCC more proximal

Question 25

Schatski ring?

Answer 25

thin mucosal membrane, found distally, typically associated w hiatus hernia

Question 26

Zenker's diverticulum

Answer 26

excessive pressure causing ballooning of weakest portion of pharynx leading to poor swallowing via weakened relaxation of cricopharyngeus (elderly)

Question 27

Eonsinophilic Oesophagitis?

Answer 27

Allergy mediated Eonsiphil infiltration of oesophageal epithelium

Question 28

Achalasia?

Answer 28

Degeneration of Myenteric Plexus and LOS inhibitory nerves causing loss of peristalsis in distal oesophagus and loss of LOS relaxation

Question 29

Scleroderma?

Answer 29

Hardening (fibrosis) of skin and connective tissue; in oesophagus affects submucosa, muscle and nerves eliminating peristalsis and LOS tone, weaking contractions leading to dysphalsia and severe reflux